Effects of angiotensin converting enzyme gene polymorphism on endothelial function in patients with essential hypertension / 中华全科医师杂志

Objective To investigate effects of angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism on endothelial function in elderly patients with essential hypertension. Methods Seventy-three elderly patients with uncomplicated essential hypertension and 55 normal elderly people as control were recruited into the study. Their humeral arterial endothelial vasodilatation function was studied with high-resolution ultrasonography and ACE I/D genotypes were determined by polymerase chain reaction (PCR) technique. Results Endothelium-dependent vasodilatation function of the three-genotype subgroups of the elderly patients with essential hypertension was significantly lower than that in the controls with the same genotypes (5.5±1.9 vs 11.9±1.3 in Ⅱ genotypa, 4.7±2.0 vs 10.9±1.6 in ID genotype and 2.9±1.9 vs 9.4±2.6 in DD genotype, with all P<0.01 ). In both groups of hypertensives and normotensives, humeral arterial endothelium-dependent vasedilatation function was significantly lower in those with DD genotype than that in those with Ⅱ genotype (2.9±1.9 vs 5.5±1.9 in hypertensive group and 9.4±2.6 vs 11.9±1.3 in control group, both P<0.05 ). Multivariate linear regression analysis showed that endothelium-dependent vasodilatation function in hypertensive elderly people correlated in linearity with their ACE genotype (P<0.01 ). Conclusions ACE gene I/D polymorphism is associated with abnormal humeral arterial endothelium-dependent vasodilatation function of humeral artery in patients with essential hypertension.

Assessment of coronary artery disease with second harmonic myocardial perfusion contrast echocardiography / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To assess the relationship between myocardial regional perfusion using second harmonic myocardial contrast echocardiography (MCE) by venous injection of Levovist and coronary artery stenosis detected by coronary angiography to determine whe ther MCE can be used to detect coronary artery disease (CAD) and its sensitivity and specificity for detecting CAD.</p><p><b>METHODS</b>Thirty-six patients who underwent coronary artery angiography and MCE formed the study groups. Ten myocardial segments (5 each in the apical two- and four-chamber views) from the images were scored for detecting myocardial perfusion as follows: 1, normal perfusion; 2, decreased perfusion; and 3, perfusion defect. The arteries were classified as normal or diseased. The diseased arteries were classified into three groups according to the perfusion scores.</p><p><b>RESULTS</b>There were significant differences in coronary diameter stenosis among the different perfusion score groups (P < 0.001). There were 10 total occluded arteries, and the myocardial perfusion scores were different because of different collateral circulation. In the normal perfusion group (Group A), the coronary diameter stenosis was 65% +/- 12%, and the myocardial perfusion score index was 1 +/- 0.00. In the decreased perfusion group (Group B), the average coronary diameter stenosis was 82% +/- 8%, and the myocardial perfusion score was 1.93 +/- 0.16. The diameter stenosis was less than 85% in 63% of the coronary arteries (including diameter stenosis < or = 75% in 12% of the vessels). The diameter stenosis was 85%-90% in 22% of the coronary arteries and > 90% in 15% of the arteries. In the perfusion defect group (Group C), the average diameter stenosis was 90% +/- 6%, and the myocardial perfusion score index was 2.89 +/- 0.24. The diameter stenosis was > or = 85% in 94% of the coronary arteries, and the diameter stenosis was < 85% and > 75% only in 6% of the coronary arteries. The overall sensitivity and specificity of MCE in identifying angiographic coronary diameter stenosis was 67% and 100%, respectively. The false negative rate was 32.6% for the 108 coronary arteries. Further subdivided analysis showed the sensitivities in Groups A, B and C were 0, 100%, and 100%, respectively. The sensitivity increased with increased lumen diameter stenosis of coronary arteries.</p><p><b>CONCLUSIONS</b>There is a close relationship between coronary artery stenosis and MCE perfusion scores. MCE with venous injection of new generation contrast can define the presence of CAD and lesion graded classifications. Some disagreements between perfusion score and coronary diameter of stenosis may indicate other factors such as different collateral circulation, which should be further investigated. As artery stenosis increases, the sensitivity of MCE is increased.</p>

Evaluation of the large arterial remodeling in elderly hypertensives by ultrasonography / 中华老年医学杂志

Objective To evaluate the vascular remodeling features in the elderly hypertensives through detecting the changes of large arterial structure and function by ultrasonography. Methods High resolution ultrasound was applied to examine 52 lightly or moderate elderly hypertensives(LMEH), 52 elderly normal subjects(EN) and 25 adult normal subjects(AN). Carotid and humeral arterial intimal-medial thickness (IMT), lumen diameter(r) and IMT/r were determined as the index for the changes of arterial structure, and the humeral arterial endothelium-dependent vasodilation and cross-sectional compliance were used to reflect the changes of arterial functions. Results Carotid IMT and lumen diameter were larger in LMEH group than those in EN group(0.97?0.21)% vs. (0.82?0.12)%, (7.41?2.13)% vs. (6.38?0.45)%, all P